Sorting machine for letters or similar flat objects



Sept. 21, 1954 G. x. LENS 2,639,657

SORTING momma FOR LETTERS OR SIMILAR FLAT OBJECTS Filed m. is, 1951 s Sheets-Sheet 1 Inventor G. LENS Attorney G. X. LENS :Sept. 21,1954

SORTING MACHINE FOR LETTERS OR S IMILAR FLAT OBJECTS 6 Sheets-Sheet 2 Filed Dec. 18, 1951 Inventor GXLEN 5 Attorney Sept. 21, 1954 s. x. LENS 2,639,657

SORTING MACHINE FOR LETTERS QR SIMILAR FLAT OBJECTS Filed Dec 18, 1951 e Sheets-Sheet s Inventor G. X. L E S Attorne y Sept. 21, 1954 G. x. LENS 2,689,657

SORTING MACHINE FOR LETTERS OR SIMILAR FLAT OBJECTS Filed Dec. 18 1951 6 Sheets-Sheet 4 Inventor G.X.LENS

A Item e y G. X. LENS Sept. 21, 1954 SORTING MACHINE FOR LETTERS OR SIMILAR FLAT OBJECTS Filed Dec. 18 1951 6 Sheets-Sheet 5 Inve ntbr G. X. L E N 5 Sept. 21, 1954 e. x. LENS 2,689,657

SORTING MACHINE FOR LETTERS OR SIMILAR FLAT QBJECTS Filed 1 390. 18, 1951 6'SheetsSheet 6 Inventor GLX. L E N S fl wi Attor'ney Patented Sept. 21, 1954 SORTING MACHINE FOR LETTERS OR SIMILAR FLAT OBJECTS Georges Xavier Lens, Antwerp, Belgium, assignor to International Standard Electric Corporation, New York, N. Y., a corporation of Delaware Application December 18, 1951, Serial No. 262,207

Claims priority, application Netherlands December 18, 1950 6 Claims.

The present invention relates to a sorting machine for letters or similarfiat objects having predetermined marginal dimensions, comprising one or more sorting positions to which these objects are supplied in a pile. Letter sorting machines of this type are known already as e. g. disclosed in the Dutch patent specification No. 61,887 in which the sorting operator takes up letters one by one with one hand and with the other hand records a code number e. g. consisting of three digits and corresponding to the destination, onto a keyboard.

In this known machine as a result of this recording operation, several members on an available carrier, connected with a conveyor chain, Were physically set into a position which was characteristic to the destination of the sorted letter. A letter-box in which this letter was finally to be deposited and which corresponded with the destination was also provided with a plurality of members arranged in a fixed position which was characteristic to this destination.

As soon as the carrier had arrived at the place of this letter-box, a flap was opened on the carrier by cooperation of both sets of members now coming into mutual contact, after which the letter arrived via a chute into the desired letterbox. Sucha machine was not only very complicated and expensive but also possessed various disadvantages.

For example, this machine caused unnecessary noise so that it became necessary to completely enclose it by sound damping material, thus making it comparatively inaccessible for inspection and maintenance. 1

Moreover, in practice it happens that the adjustable members on the carriers provide so many chances for inaccurate operation that a number of maintenance people must always be present to clear the occurring faults.

The sorting speedto be attainedis, amongst other things, dependent upon the time needed by the sorter to effect his manipulations and this time is lengthened individually by the necessity for taking up the letters and depositing them manually in an outlet slot. These manipulations must always be terminated at the end of fixed recurrent time-intervals. From a hygienic point of view this manual handling of the letters is also undesirable An object of the invention is to improve -a machine of the type under consideration. The

invention takes advantage of the fact that a higher sorting, speed may be obtained if the 2 manipulations of the sorter are solely limited to depressing the keys on the keyboard for which the sorter has now both hands free since he does not need to handle the letters.

Moreover the invention is preferably used in a system in which all lette -holders of the main conveyor chain are common to the sorters; are identical in construction and need not include any adjustable members having a physical characteristic indicative of the destination and furthermore all receptacles into which the letters are deposited are also identical and do not include any adjustable members having physical charac- 1teristics indicative of the destination of these etters.

While in the above-mentioned well known sort- I ing machine, the sorters had to be located on a high platform, a considerable improvement may be obtained if the sorting positions can be normally provided within the vicinity of the lowest part of the common conveyor chain, which then involves, however, the problem of delivering the sorted letters, via an intermediate conveying device, into those letter-holders of the main chain which successively become available for a sorter under consideration.

A further object of the invention is to restrict the total dimensions of the sorting machine as much as possible, since usually, thesemachines are installed in existing buildings.

A further object of the invention is to manufacture the sorting machine from light moving components so that a economyin driving power is obtained.

A proper coordination of the various conveying devices forms one of the main problems which has been solved by my invention in a simple and reliable manner.

In an embodiment of the invention, the sorting machine may comprise in combination with a first conveying device individual for each s'orting position, which automatically takes off the objects, e. g. letters, one by one from the automatically advanced pile, subsequently moves the letter in front of the sorter and at the end comprises a transfer mechanism, and a second, continuously moved, intermediate conveying device which separately receives the objects from the transfer mechanism and separately conveys them along toward an equal speed, continuously moved, third conveying device; an arrangement, in a fixed zone, for transferring the object from the second conveying device to the third device which delivers it atthe place of destination, the third conveying device being common to a plurality of first and second conveying devices which individually correspond to each other and having no destination indicative indicia thereon.

In accordance with a feature of the invention the carrying members of the second and third devices are constituted by box-shaped letterholders each having two movable flaps.

In accordance with a further feature of the invention, the conjunction between a letter-' holder of the second conveying device and another letter-holder of the third conveying device takes place in'a predetermined zone in space, which is identical for each sorters position and which is sufliciently large to permit the letterholder of the third conveying device to open the letter-holder of the second conveying device'at the conjunction point in order to receive the letter or object contained by the latter.

The chain of the common conveying device extends in serpentine-fashion and reeves so as to present odd and even straight portions, which are mutually parallel, according to the "sense of displacement.

In accordance with'an important'ieature of the invention, the letter-holders of this chain are provided with means (e. g.idlers) guided along guiding paths such that'the letter-holders passing in the even straight portions are symmetrically inclined with respect to the letter-holders in the odd straight portions and in such a way that this inclination presents an optimum angle with respect to "the sense of translation or Said letter-holder's.

Furthermore,both naps of these last-mentioned letter-holders are so arranged that depending upon the position of the letter-holder, they may function as an inlet'fiap or outlet flap, in accordance with a feature of the invention.

electromagnet is arranged at each destinationto control the opening of an outlet flap of theletter-hol'der of the common conveyor chain when the destination is reached, by operating a latch associated with the iiap. These electromagnets are energized under control of signals from the sorters keyboard, tooperate the releasing latch at the time the letter holder reaches its desired destination. V

In accordance with a further feature of the invention, the said electromagnet operates the latch of that flapwl ichfin the position considered, acts as an outlet flap while both latches are preferably controlled by one common spring.

The invention be further described with reference to the accompanying drawings for a preferredembodiment of the invention which has been shown by way of example, and in which Fig. 1 represents a perspective view of the main parts of the sorting machine.

Fig. 2 shows a diagrammatic location of the main chain of the third conveying device.

Figs. 3 and 4 respectively show a plan view and a sideelevation of a letter-holder belonging to this third conveying device.

7 Fig. 5 is a perspective view of the location of the rotating conveyor belt and the receptacles of the destinations, while,

Fig. 6 represents a side elevation of a plurality of receptacles together with an alarm arrangement, common to a grouper receptacles.

For convenience, the objects to be sorted will be called letters, although it shouldbe clearly understood that this invention may be adapted for the sorting of any type of objects'having predetermined marginaldimensions.

Since various parts of the sorting machine form the subject matter of inventions to be described in separate copending patent applications, a brief description of those parts :is deemed sufficient.

In Fig. l, the pile of letters is placed at the right-hand side of each sorter and these letters are automatically advanced by means diagrammatically indicated by I. One letter at a time is brought from this pile into a U-shaped channel 3 by means of a pneumatic suction member 2 whereupon this letter is led through this channel, with the aid of an'endless chain t provided with fingers 5 mounted at regular intervals, along the sorter in an intermittent movement, wherein each 7 of the letters are halted for a predetermined time in the course-of its travel through the channel. During-this stopping period, the sorter need not touch the letters by hand, but may read the destination so as to be ready to subsequently record a code number corresponding to the destination on a keyboard 6. 'In'any event, this'recordin of the code number must be terminated at the moment that the next letter again momentarily stops in front of the sorter.

For a noi'mally'trained sorter, the sorting'speed of the machine may be increased because this speed largely depends on the time required by the sorter to read the destination, to mentally translate the destination to a code number and to depress the keys for registering the code number in accordance with this-destination.

Subsequently, a transfer mechanism 1 arranged as a turnstile, is arranged to receive one letter at a tim from the chain 4 and enables the letters to be delivere one by one to a second and intermediate conveying device 8, comprising four letter-holders 5) which are continuously moved around by endless chains.

As soon as the letter-holder 9 whose movable side flap is closed after reception of thelletter from the transfer mechanism I when a roller (not shown) connected to a movable side flap 8a touches an idler 812 located at a fixed point adjacent to the path of the'letter -holders to cause closure'of the movable side flap 8a. When the holder Q-comes in register with letter-holder ll of the third conveying device, the bottom flap of the letter-holder 9 is automatically opened and the letter falls in the same position into :the letter-holder I I, then opened at the top and which obviously is closed atthe bottom beforereaching this receiving point. In-this figure, the letterholder lflhas just broken the contact with the letter-holder l l In order to simplify the construction, it was deemed advantageous to make the sorters position to a'certain extent, independent of themain body of the machine. This necessitated .the use of an intermediate mechanismhaving some flexibility. The transfer by gravity of objects to be sorted bein most economical, involved the 'following considerations: (1) The descent of an object was required to be guided; (2) the possible-variation in dimensions'of objects or letters; (3) .theresistance'of the air; (4) the course fol lowedby a letter-holder 9 during the dropping of the said letter.

a predetermined point, here-diagrammati cally indicated-by 1 2, 'whichmay be a slanting stri adjacent to the path of theth'irdconveyor device, the upper flaps of the letter-holders H are closed and then the letter-holders commence their displacement along five superimposed levels eachofwhich-hasbeenallotted to-ieedlette'rs to 6i) receptacles, each receptacle representing a different destination.

Since this embodiment has been designed for four sorting positions, it is clear that each fourth, eighth, twelfth, etc. letter-holder is put at the disposal of a certain sorter while the intermediate letter-holders are similarly put at the disposal of the second, third and fourth sorter respectively. j i

It may be seen from Fig. 1 that, as long as theletter-holders' H pass the positioning track, they are all in a vertical position. This intermediate transferconveyor system is more fully described in my copending application, Serial No. 262,209, filed December 18, 1951.

Though the further details of the construction of the letter-holders of the common conveyor will be described with reference to other figures, it may be suflicient to state here that they are carried by two main chains I3. At each side of the letter-holder there is provided an idler l4 rolling along a guide path or track l5 'while at one side there are provided two otherrollers I6 and [1 respectively, moving along the guide paths or tracks l8 and 19 respectively.

The chains are secured by extensions of the shafts of the inner idlers.

Common conveying device This conveying device consists of a long, double, endless main chain, which in the embodiment shown, comprises 627 letter-holders which are provided at regular intervals. These letterholders, as set out above, are all identical and do not carry any settable members having physical characteristics indicative of the destination to which the letter is to be sent. In order to save space the 300 receptacles corresponding to the destinations of the letters are mounted in five horizontal superimposed rows. The main chain in addition to the lowermost positioning track 20 is adapted to be moved along five horizontal paths corresponding to the five rows in serpentine fashion which, in Fig. 2, have been indicated respectively by 2|, 22, 23, 24, 25. The tracks 22 and 24 may be called the even tracks and 2|, 23 and 25 thefodd tracks.

The chains are externally driven by means of intermediate chains and suitable gear wheels, which at each side are provided with an idler of elastic and sound damping material, while, moreover, two further idlers are provided at one side. 1 1 i l ,Only while passing the positionin track are theletter-holders in a vertical position for the reception, of the letters from the intermediate conveying device. Both carrying rollers 14 roll along the paths 15, while the idlers i6 and IT roll along the guide paths l8 and [9. These guide paths may, for example, consist of angle irons.

After closure of the top flap of the letterholders, they may take a different position with respect to the vertical, and they are brought into a slanting position during their movement along each of the paths 2l25, in which they are transported via one idler at each side, one of the guiding rollers l6 or I! controllin the direction of slant of the holders. This not only results in a reduction of the total height of the machine, since the slanted holder takes up less head room than a vertical holder but at the same time one guide path or rail may be dispensed with. Only when passing'the turning points such as 26, are the letter-holders required to be guided by both rollers l6 and H, after which the slanting position of the letter-holders, upon reaching the next upper path traversed in the. reverse direction, is reversed in direction.

After leaving the upper path, the letter-holders described hereinafter), at a suitable, constant angle of incidence with respect to the sense of translation of the letter-holders.

It is further to be noted that when the letter holders of the main chain reach the track 20,

the upper flaps must be opened whereas the lower flaps must be closed in order to retain. the letters to be delivered to the holders.

Usually the opening of the upper flaps is controlled by a hook-shaped member along the path of the chain and fixed with respect thereto (not shown) beyond the last receptacle (N300), whereas the closing of the lower flaps, in so far as needed, is controlled by a wedge-shaped strip which contacts the holder, both opening member and closing wedge being adjacent the path of the chain and fixed with respect thereto. Before the letter-holders leave the track 20, the upper flaps must be closed and this is effected by the contacting of the holder against a wedge-shaped strip placed along the path or the chain and fixed with respect thereto.

It is also shown therein, that between the positioning track and the first superimposed part of the main chain, a larger distance is needed than between the next adjacent paths, because the intermediate conveying device is also mounted in that space.

Upon arrival of a holder at the receptacle corresponding to the destination of a letter transported thereby, the letter may be released by energising an electromagnet individual to the receptacle and indicated by 21 in Figs. 5 and 6. One of each of these relays is provided at each of the receptacles and connected over suitable wiring circuits with the sorter keyboards. Upon operation of the keys to designate the terminal receptacle to receive a letter, signals are despatched which will serve to operate the relay associated with the designated receptacle at the time the corresponding letter reaches it. The timing is properly co-ordinated with the various sorter positions to operate the latch regardless of which sorter despatches the letter. The details of the signal and storage circuits for operating the unlatching relays forms no part of this invention and therefore is not illustrated. For details of such a circuit reference is made to an application of M. Neyt, Serial No. 229,393, filed June 1, 1951. The aforementioned copending application and this application are assigned to the same assignee. The flap which in that positionof the letter-holder is moment, is now opened and the letter falls on a horizontal endless conveyor belt 28 provided below the letter-holders and made out of braided metal wire, which is kept tensioned between rollers 29 the lowermost flap at that 7. and :is: continuously driven by suitable means which ha-venot been shown ina directiontransverseto thedirection of travel of the chain.

Thexconveyor belt28 has such width that-it is common to e. g. four adjacent terminal receptacles.

In order to maintain the letters separated on their further travel to their-destination receptacles, lateral partitions :are provided, indicated here by 30'. As soon as the, letter bas arrived at the end of the conveyor belt'it is dropped into .achute 3i terminating into the upper part of the rear wallof thereceptacle 32.

Since the receptacles form one continuous front, the bearing and driving of these conveyor belts must be such that as little space as possible is lost in the direction of width.

Since the height ofthe rectangular receptacles need not correspond with the vertical distance between two. successive chains, the chutes of the vertically aligned receptacles are not necessarily parallelto each other.

It will be seen from Fig. '6, which, in fact, should be turned to the right by 90, that the chutes of the three upperreceptacles consistof two contiguous straight portions for a substantially same angle of incidence of the letters.

Before being permitted to fall into the lower part of a receptacle, the letter passes afiap 33 pivoting around a horizontal shaft. The flaps of :two adjacent vertical rows, thus for a total of ten receptacles, are connected .in common to an .alarm indicated by .34 in Fig. 6, which warns the attendant that the flap has been tilted too far in one or more receptacles, in other words that the receptacle is completely filled.

All the cooperating flaps may,.for example, be coupled by these rods which control the operationof the common alarm device 34. One of these rods is shown in Fig. 6 connected to a coil of the .alarm device.

The letters arrive in the receptacles allin the identical position, i. e. either with the address upwards or with the address downwards and they may be removed by opening the front covers 35, which covers are hinged around their upper edges, and which front covers may be pivoted open by means of the handle 3'6. Thisfront is slotted at 3'! so as to permit the letters .tobe observed.

The construction of the letter-holders 33 itself is shown in Figs. 3 and. 4.

'Asshown in Fig. 4, the supporting structure of one side of the holder consists of a triangular shaped sideplate 33, in which the main shaft M3 is mounted and on which shaft the carrying rollers {4 are secured. The extension-Mia of this shaftprojects through links of the main chain.

The letter-holders are arranged .as flat boxes M of rectangular shape,;thelength and width of whichare determined by the maximum dimensionof the letters to be sorted.

At-the top and bottom, flaps 4-2, '43 are provided, respectively, .each carrying a hook '44, M pivoting respectively around the pivots 45, 46, which pivots areamxed to side 4 la of theholder. Latches MAT-engaging these books 41, 41' are kept in the operated position bys-prings 48, 43.

A single spring (not shown) may be used to bring the upper or lower flaps in the opene'dpoe sition as soon as a force in the direction, of the flap is exerted on the latch, which is arranged as a bell crank, because the bent end 449, 49 of the latch lever is rotated by an armature lever of transferred to the chain for the last sorter and,

before the letter-holders are conveyed upwardly to the next path, a member as mentioned aboveis located alongside the track, which closes the upper flaps which remained opened.

Theletter-holders. which, as stated above, are

all identical, may be made as simple andlight as possible, since they need only convey "but, a s'ingle'letter at, a time.

While I'have described above the principles of my invention in connection with specific ape paratus, it is to beclearly understood that this description ismade only by way of exampleand not as a limitation'to the scope of my invention.

I claim:

1. Ina sorting device for 'flat objects, having, a continuous conveyorymeans for reeving said conveyor back and forthin difierent horizontal directions, terminal object receivers for receiving objects from said conveyor positioned under said conveyor-in each directionof travel, and a plurality of substantially identical object carriers mounted on said conveyor -for movement past said object receivers; a construction for'assuring proper delivery of objects by said carrie'rs to said object receivers regardless of the direction of travel of said carriers comprising flatsided object holders forming said carriers, means pivotally mounting said carriers to said -conveyor, tilting means attached to said holders, means fixed with respect to said conveyor for cooperating with saidtilt-ing means, said fixedmeans and said tilting means adapted to cooperate to maintain the flat sides of said holders at an acuteangleto-said conveyor wherebyopposite ends of said holder will'be selectively directed toward said object receivers dependent upon the direction of travel of said conveyor, movable-closure means at opposite ends of said holders to retain objects therein during conveyancean'd means for selectively opening the closure 'means directed toward a predeterminedobject receiver upon the desired. object holder reaching said predetermined object receiver.

2. A sorting device according to claim '1, wherein said means for selectively opening said closure members comprise separate latch means for the two closure members mounted on said object holders for latching said closure memhere in closed position and means at each object receiver'position selectively operative to release the latch means associated with the lower of .said closure members.

3. A sorting device according to claim 1, wherein'said object receiver-s comprise, aterminal conveyor movable transversely of said continuous conveyor and mounted below it, and means dividing'the surface of said terminal conveyor 1ongitudinally thereof to provide a plurality'oi object receiving areas in its-transverse dimension.

i4. A'sortingdeviceaccording to claim 1, whereinsaid means for maintaining said objectholders at. an-angle comprise spaced rollers mounted on said holders and guiding means forsaidrollers mounted on opposite sides ofsaid oonveyonalong said two directions.

5. A device according to:c1aim-4,-further comprising other guiding means spaced from said conveyor and positioned at the points where said conveyor reverses direction of travel, said other guiding means co-operating with said rollers to assure proper alignment for the next successive direction of travel.

6. A sorting device according to claim 5, further comprising a loading position, said conveyor extending for a distance longitudinally thereof, and loading guide means adjacent said 10 conveyor in said loading position and co-operating with said rollers to retain said holders substantially perpendicular to said conveyor during traversal of said loading position.

References Cited in the file of this patent UNITED STATES PATENTS 

